Attempts have been made in the past to produce engines which utilize a portion of the cylinders for generating a hydrogen rich exhaust gas which is then combined with hydrocarbon fuel in a carburetor and delivered to the remaining cylinders of the engine for combustion, One such system is illustrated in U.S. Pat. No. 4,041,910, issued to John Houseman on Aug. 16, 1977. A similar system is illustrated in U.S. Pat. No. 4,108,114, issued to Katuaki Kosaka, et al. on Aug. 22, 1978. In each of the above patents, the exhaust gas is virtually untreated and is returned to the cylinder for the complete combustion of the unburned hydrocarbons and any free hydrogen that may be contained therein.
U.S. Pat. No. 4,059,076 issued to Katuaki Kosaka, et al. on Nov. 22, 1977, illustrates use of a separate engine for generating a hydrogen rich exhaust gas which is subsequently burned in the main power engine. In the system described in the '076 patent, the exhaust gas is mixed with hydrocarbon fuel and then passed through a catalytic converter prior to being delivered to the main power engine.
An object of this invention is to provide an improved fuel system and combustion process for use with both reciprocating and gas turbine engines wherein hydrogen rich exhaust gas is generated in the engine, passed through a water-gas shift catalyst to further increase its hydrogen content, then mixed with a lean hydrocarbon fuel for burning in the remainder of the engine.